Nanostructured zinc oxide films grown via microwave-assisted H2O oxidation for perovskite solar cells

ZnO is well-known to be one of the most significant metal oxides that can be used as an electron-transporting layer (ETL) in solar cells. Hence, developing efficient and low temperature protocols have been the spotlight of numerous studies to form nanostructured ZnO films. Herein, the growth of nanostructured ZnO films via low-temperature microwave-assisted H2O oxidation is presented. ZnO nanorods developed after 30 min of microwave irradiation. Then the nanorods evolved to nanoparticles in longer irradiation time. Raman scattering spectra of these nanostructures displayed intense E2-mode peaks confirming their high-quality wurtzite crystal structure. All the samples have an average transmittance of ∼ 80%, which demonstrates their potential as ETL for solar cells. Our results highlight the potential of the integration of microwave technology with H2O oxidation as a fast, low temperature and sustainable process of developing ZnO nanomaterials that can be used for flexible ZnO-based electronics.